Non monadic low level support stuff for the MFlow application server.
(See MFlow.Form for the higher level interfaces)
it implements an scheduler of queued Processable messages that are served according with
the source identification and the verb invoked.
The scheduler executed the appropriate workflow (using the workflow package).
The workflow may send additional messages to the source, identified by a Token
. The computation state is optionally logged and recovered.

The message communication is trough polimorphic, monoidal queues.
There is no asumption about message codification, so instantiations
of this scheduler for different infrastructures is possible,
including non-Web based ones as long as they support or emulate cookies.

MFlow.Hack is an instantiation for the Hack interface in a Web context.

stateless and transient server processeses are also possible. stateless are request-response
with no intermediate messaging dialog. transient processes have no persistent
state, so they restart anew after a timeout or a crash.